Flexible photovoltaic array with integrated wiring and control circuitry, and associated methods

ABSTRACT

A flexible photovoltaic module for converting light into electricity includes a plurality of photovoltaic cells, a wiring harness, and a connection subsystem. The plurality of photovoltaic cells are electrically interconnected to form a positive node for supplying current to a load and a negative node for receiving current from the load. The wiring harness includes a plurality of flexible electrical conductors, each electrical conductor being electrically isolated within the wiring harness. The connection subsystem is operable to selectively connect the positive node to one of the electrical conductors of the wiring harness. A plurality of flexible photovoltaic modules may be connected to form a photovoltaic array.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a divisional application of U.S. patent applicationSer. No. 11/877,625, filed Oct. 23, 2007, now U.S. Pat. No. 7,812,247which claims benefit of priority to U.S. Provisional Patent ApplicationSer. No. 60/853,609 filed 23 Oct. 2006 and U.S. Provisional PatentApplication Ser. No. 60/853,610 filed 23 Oct. 2006. Each of theaforementioned applications are incorporated herein by reference.

BACKGROUND

Photovoltaic solar power systems are an increasingly attractivealternative to using legacy power generating technologies due to growingconcerns about the sustainability and cost of such legacy technologies.However, limitations of commercially available photovoltaic solar powersystems have prevented their widespread acceptance and use.

Conventional photovoltaic solar power systems are typically complicatedand expensive to install. They are often weighty and cumbersome, and mayrequire special support structures. For example, when a conventionalsolar power system is installed on a building's roof, special supportstructures may be required to support the power system. Additionally, aconventional solar power system may significantly increase a roofsweight and/or wind load when installed on the roof. In some cases, thequantity of modules needed to generate the desired power would exceedthe roof's rated structural limits, thereby preventing the installationof the required photovoltaic solar power system.

The installation of such conventional solar power systems is in itselfproblematic. Conventional solar power systems are typically built from alarge number of rigid, heavy photovoltaic modules of relatively lowvoltage and power, that are frequently difficult to transport andmaneuver. The photovoltaic modules must be delivered to an installationsite, individually disposed in their proper locations at theinstallation site, and individually connected with cables, wires,breakers, boxes, combiners, and/or connectors. Furthermore, due to theirlow voltage and relatively low power output, there is generally a needto wire a large number of photovoltaic modules in series and/or inparallel. Photovoltaic modules need to be wired in series to achieve adesired open circuit output voltage, and photovoltaic modules need to bewired in parallel to achieve a given current rating for the overallsystem. Typically, for a given circuit, a plurality of modules areconnected in series, referred to as a string, to achieve the desiredvoltage, and in turn, several of these strings are connected in parallelto achieve the desired current for this circuit. Therefore, installationof conventional solar power systems is generally labor intensive,complex, and costly.

Additionally, the multitude of components required in traditional solarpower systems (e.g., cables, wires, breakers, boxes, combiners, andconnectors) increase the complexity of the system, which may decreaseits reliability and/or increase its maintenance requirements.Furthermore, the cost of such multitude of components is oftensignificant, thereby contributing to the relative costliness oftraditional solar power systems.

Conventional photovoltaic solar power systems are also frequentlydifficult to adapt to topographical features of real world installationsites, thereby limiting their adoption. Installation sites often containobstructions (e.g., a roof may contain vents, skylights, heating,ventilation and air conditioning (HVAC) equipment) which limit acontiguous area available for disposing photovoltaic modules thereon.Further complicating these installations is that by necessity, the PVarray must be oriented to accept the sun's rays most directly, while thebuilding's rooftop is not always oriented to easily accommodate thisrequirement. Accordingly, solar power systems must be built around suchobstructions. However, components of conventional solar power systemsgenerally have fixed dimensions, which prevents them from beingcustomized to a particular installation site to work aroundobstructions. For example, if a roofs surface is broken up by twoplumbing vents, conventional solar power system components may not beavailable in suitable dimensions to be disposed between the plumbingvents.

Furthermore, as described above, a certain quantity of traditionalphotovoltaic modules of conventional solar power systems must beconnected in series to achieve a desired output voltage, therebylimiting flexibility in disposing the components in an installationsite. For example, consider a roof broken up by a chimney. In order towork around the chimney while still connecting enough traditionalphotovoltaic modules in series to achieve a required open circuit outputvoltage, one or more component photovoltaic modules in a string may beplaced away from its fellow, series-connected photovoltaic modules. Thisrequires additional wiring, and may result in sub-optimal coverage overan installation site.

SUMMARY

A photovoltaic array includes a flexible first photovoltaic module and aflexible second photovoltaic module for converting light intoelectricity. The first photovoltaic module has a positive node forsupplying electric current to a load and a negative node for receivingelectric current from the load. The first photovoltaic module includes afirst wiring harness having a plurality of flexible electricalconductors, each electrical conductor being electrically isolated fromeach other electrical conductor within the first wiring harness. Thepositive node of the first photovoltaic module is electrically connectedto one of the electrical conductors of the first wiring harness, and theremaining electrical conductors of the first wiring harness areelectrically isolated from the positive and negative nodes of the firstphotovoltaic module.

The second photovoltaic module has a positive node for supplyingelectric current to a load and a negative node for receiving electriccurrent from the load. The second photovoltaic module includes a secondwiring harness having a plurality of flexible electrical conductorscorresponding to the electrical conductors of the first wiring harness.Each electrical conductor is electrically isolated from each otherelectrical conductor within the second wiring harness. The positive nodeof the second photovoltaic module is electrically connected to one ofthe electrical conductors of the second wiring harness, and theremaining electrical conductors of the second wiring harness areelectrically isolated from the positive and negative nodes of the secondphotovoltaic module. The electrical conductors of the first wiringharness are electrically connected to the corresponding electricalconductors of the second wiring harness.

A flexible photovoltaic module for converting light into electricityincludes a plurality of photovoltaic cells, a wiring harness, and aconnection subsystem. The plurality of photovoltaic cells areelectrically interconnected to form a positive node for supplyingcurrent to a load and a negative node for receiving current from theload. The wiring harness includes a plurality of flexible electricalconductors, each electrical conductor being electrically isolated withinthe wiring harness. The connection subsystem is operable to selectivelyconnect the positive node to one of the electrical conductors of thewiring harness.

A process for forming a solar power electrical generation system at aninstallation site includes the following steps. A first photovoltaicmodule is disposed at the installation site, where the firstphotovoltaic module includes a first wiring harness having a pluralityof first electrical conductors and a first control box in electricalcommunication with the first electrical conductors. A secondphotovoltaic module is also disposed at the installation site proximateto the first photovoltaic module. The second photovoltaic moduleincludes a second wiring harness having a plurality of second electricalconductors corresponding to the first electrical conductors. The secondphotovoltaic module further includes a second control box in electricalcommunication with the second electrical conductors.

The second electrical conductors of the second wiring harness areelectrically connected to the corresponding first electrical conductorsof the first wiring harness using the control box as a connection point.A positive node of the first photovoltaic module is electricallyconnected to one of the first electrical conductors of the first wiringharness using a selector switch of the first control box. A positivenode of the second photovoltaic module is electrically connected to oneof the second electrical conductors of the second wiring harness using aselector switch of the second control box.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a top plan view of one solar power generation system,according to an embodiment.

FIG. 2 is a top plan view of one flexible photovoltaic module, accordingto an embodiment.

FIG. 3 is a top cross sectional view of one embodiment of the wiringharness of the photovoltaic module of FIG. 2.

FIG. 4 is a block diagram of one control box for interconnecting aplurality of photovoltaic modules, according to an embodiment.

FIG. 5 is a top plan view of an array of the photovoltaic modules ofFIG. 2, according to an embodiment.

FIG. 6 is a top plan view of one solar power generation system,according to an embodiment.

FIG. 7 is an electrical schematic of one three circuit embodiment of thesolar power generation system of FIG. 6.

FIG. 8 is an exploded side view of one flexible photovoltaic module,according to an embodiment.

FIG. 9 is an exploded side view of one flexible photovoltaic module,according to an embodiment.

FIG. 10 schematically shows three embodiments of the photovoltaicsubmodule assembly of FIGS. 8 and 9.

FIG. 11 is an exploded perspective view of one solar power generationsystem, according to an embodiment.

FIG. 12 is a side perspective view of one supporting structure,according to an embodiment.

DETAILED DESCRIPTION

It is noted that, for purposes of illustrative clarity, certain elementsin the drawings may not be drawn to scale. Specific instances of an itemmay be referred to by use of a numeral in parentheses (e.g.,photovoltaic module 102(1)) while numerals without parentheses refer toany such item (e.g., photovoltaic modules 102).

FIG. 1 is a top plan view of one solar power generation system 100 whichgenerates direct current or alternating current electricity fromsunlight or other forms of light (e.g., light from an artificial lightsource). Solar power generation system 100 powers, for example, load104, and is installed in an installation area 114. Examples ofinstallation area 114 include a building's roof, an outer surface of avehicle (e.g., a spacecraft), and a solar power farm. Ideally,installation area 114 is free of obstructions that interfere withplacement of components of solar power generation system 100. However,installation area 114 may, and often does, contain obstructions. Forexample, FIG. 1 illustrates installation area 114 including obstructions106 and 108. If installation area 114 is a building's roof, obstructions106 and 108 could be skylights, HVAC units, chimneys, plumbing vents,etc. As another example, if installation area 114 is considered to be aspacecraft's outer surface, obstructions 106 and 108 could be consideredto be communication antennas, windows, propulsion equipment, etc.

Solar power generation system 100 includes at least one photovoltaicmodule 102, each of which converts incident light into direct current oralternating current electricity. Each photovoltaic module 102 has apositive node through which the photovoltaic module provides electriccurrent to a load, and each photovoltaic module 102 has a correspondingnegative node through which the photovoltaic module receives returnelectric current from the load. Positive nodes of each photovoltaicmodule 102 are electrically connected to load 104 via connectors 110,and negative nodes of each photovoltaic module 102 are connected to load104 via connectors 112.

Solar power generation system 100 is illustrated as including fourphotovoltaic modules 102(1), 102(2), 102(3), and 102(4). However, solarpower generation system 100 is modular in that photovoltaic modules 102may be added to or removed from solar power generation system 100 as itsapplication requires. For example, if an application requires additionalelectric power, additional photovoltaic modules 102 may be added topower generation system 100. Conversely, if an application requires lesselectric power or an installation area 114 does not contain sufficientspace to dispose each of photovoltaic modules 102(1), 102(2), 102(3),and 102(4), one or more photovoltaic modules 102 may be removed.

As discussed below, embodiments of photovoltaic modules 102 areflexible, allowing for placement of photovoltaic modules 102 onnon-planar surfaces. Such optional flexibility of photovoltaic modules102 may also facilitate their transportation and installation—forexample, they may be rolled-up for ease of transportation. Furthermore,embodiments of photovoltaic modules 102 have customizable lengths and/orwidths allowing photovoltaic modules 102 to be sized for installationsite 114. For example, as illustrated in FIG. 1, photovoltaic module102(2) has a length L2 that is shorter than length L1 of photovoltaicmodule 102(1) in order to accommodate obstruction 106. Similarly,photovoltaic modules 102(3) and 102(4) have respective lengths L3 and L4that are sufficiently short to accommodate obstruction 108.

Embodiments of photovoltaic modules 102 have essentially identical opencircuit output voltages despite variations in their dimensions.Photovoltaic modules 102(1), 102(2), 102(3) and 102(4), for example,have essentially the same open circuit output voltage even though theyhave different lengths. This feature may advantageously reduce oreliminate the need to electrically connect photovoltaic modules 102 inseries, thereby reducing installation complexity and cost. Embodimentsof photovoltaic modules 102 also have a relatively high open circuitoutput voltage (e.g., 480 volts or 600 volts), which may also eliminatethe need to connect photovoltaic modules in series. For example, FIG. 1illustrates each photovoltaic module 102 being electrically connected inparallel to load 104 by connectors 110 and 112. However, it should benoted that if photovoltaic modules 102 have different dimensions, theymay have different maximum current capabilities because currentcapability is commonly proportional to surface area of the photovoltaicmodule.

FIG. 2 is a top plan view of one flexible photovoltaic module 200, whichis an embodiment of photovoltaic module 102 of FIG. 1. Photovoltaicmodule 200 includes one or more photovoltaic submodules 208, wiringharness 204, and ground wiring harness 206. Embodiments of photovoltaicmodule 200 may be capable of producing an output power of up to 5,000watts, and embodiments of photovoltaic module 200 may have a relativelyhigh open circuit output voltage (e.g., 360 volts, 480 volts, or 600volts) which may eliminate the need connect a plurality of photovoltaicmodules 200 in series to achieve a desired open circuit output voltage.While it is possible to create photovoltaic modules with similar highpower and/or high open circuit output voltage ratings using traditional,rigid PV technology, such photovoltaic modules would be completelyimpractical, both in terms of dimensions and weight. In contrast,embodiments of photovoltaic module 200 with high power and/or high opencircuit output voltage ratings may be rolled-up in a compact form forease of transportation; furthermore, such embodiments may weighsignificantly less that rigid photovoltaic modules with similar outputcharacteristics.

In embodiments of photovoltaic module 200, photovoltaic submodules 208are thin-film photovoltaic devices, which may created of materialsincluding, but not limited to, copper-indium-gallium-selenium (CIGS),copper-indium-gallium-selenium-sulfur (CIGSS),copper-indium-aluminum-selenium (CIAS),copper-indium-gallium-aluminum-selenium (CIGAS),copper-indium-gallium-aluminum-selenium-sulphur (CIGASS),cadmium-telluride (CdTe), amorphous silicon (a-Si), or combinationsthereof. Furthermore, in embodiments of photovoltaic module 200,photovoltaic submodules 208 are monolithically integrated onto a commonsubstrate. For example, one embodiment of photovoltaic module 200 has asingle monolithically-integrated thin-film photovoltaic submodule 208with multiple CIGS cells. As another example, another embodiment ofphotovoltaic module 200 includes a plurality of discrete, interconnectedphotovoltaic submodules 208 of photovoltaic cells that are printed ormanufactured (e.g., by a roll-to-roll process) on a substrate common tothe submodule.

In embodiments where photovoltaic submodules 208 are thin-filmmonolithically-integrated photovoltaic devices, the monolithicintegration process may be computer controlled. A multitude of differentmonolithic integration patterns may be chosen to provide a given opencircuit voltage and maximum current rating. Scribes delineating aplurality of photovoltaic submodules 208 on a common substrate may beplaced parallel and/or perpendicular to the web transport direction.Photovoltaic submodules 208 may be the size of the entire photovoltaicmodule 200 such that photovoltaic module 200 has one submodule 208, orphotovoltaic submodules 208 may be scribed into smaller units on acommon substrate. An optimum size and configuration of submodules 208 isdetermined, for example, through cost and/or performance modeling of thesubmodules.

Conductive bus bars 210 electrically connect photovoltaic submodules 208to each other in a variety of configurations (e.g., parallel and/orseries) to establish positive node 228 and negative node 230 ofphotovoltaic module 200. Photovoltaic module 200 supplies current to aload from positive node 228, and photovoltaic module 200 receivescorresponding return current from the load from negative node 230. Theconfiguration of bus bars 210 (e.g., whether photovoltaic submodules 208are connected in parallel and/or series) partially determines theelectrical characteristics of photovoltaic module 200. Bus bars 210, forexample, connect photovoltaic submodules 208 to a ground conductor 212formed with (e.g., sealed in) ground harness/jumper 206—thus, negativenode 230 is electrically connected to ground conductor 212. Bus bars210, for example, also electrically connect the photovoltaic submodules208 to lead 214, which in turn may be connected to a flexible electricalconductor 216 within wiring harness 204 by a connection subsystem (notshown in FIG. 2), as discussed below. Thus, positive node 228 iselectrically connected to lead 214 which in turn may be electricallyconnected to a flexible conductor 216.

Photovoltaic module 200 is illustrated in FIG. 2 as including fivephotovoltaic submodules 208 electrically connected in parallel by busbars 210. Accordingly, the open circuit output voltage of photovoltaicmodule 200 is equal to the open circuit output voltage of eachphotovoltaic submodule 208, and the maximum current capability ofphotovoltaic module 200 is equal to five times the maximum currentcapability of each photovoltaic submodule 208. However, theconfiguration of bus bars 210 and photovoltaic submodules 208 shown inFIG. 1 is exemplary, and non-limiting. Photovoltaic submodules 208 maybe electrically connected in series instead of in parallel to increasethe open circuit output voltage of photovoltaic module 200. For example,three photovoltaic submodules 208, each having an open circuit outputvoltage of 120 volts, may be electrically connected in series such thatphotovoltaic module 200 has an open circuit output voltage of 360 voltsand a maximum current capability equal to that of each photovoltaicsubmodule 208. Additionally, photovoltaic module 200 may include someinstances of photovoltaic submodules 208 electrically connected inparallel and some instances of photovoltaic submodules 208 electricallyconnected in series to increase both the open circuit output voltage andmaximum current capability of photovoltaic module 200. In all thesecases, these submodules can be discrete or patterned on a singlesubstrate. Furthermore, as noted above, embodiments of photovoltaicmodule 200 may contain solely one photovoltaic submodule 208.

In some applications of photovoltaic module 200, it is desired to have arelatively low voltage power supply available for housekeepingfunctions. In such embodiments, photovoltaic module 200 may include alow voltage tap across a subset of the module's photovoltaic cells toprovide the low voltage power supply. The low voltage tap may connect toeither positive node 228 or negative node 230 and an intermediate node,or the low voltage tap may connect to two intermediate nodes (i.e., thelow voltage tap may be floating). For example, an embodiment ofphotovoltaic module 200 has an open circuit output voltage of 600 volts,but the module also requires an 18 volt power supply to powerhousekeeping (e.g., control and/or diagnostic) equipment. This exemplarymodule has 1,200 photovoltaic cells connected in series, where eachphotovoltaic cell has an open circuit output voltage of 0.5 volts suchthat the module's open circuit output voltage is 600 volts. The lowvoltage tap is this exemplary module is connected across 36 of the 1,200photovoltaic cells to provide the 18 volt power supply.

Alternately, embodiments of photovoltaic module 200 include a DC-to-DCconverter for powering a low voltage tap. In such embodiments, theDC-to-DC converter is powered from some or all of the photovoltaic cellsof photovoltaic module 200. Further, as discussed below, embodiments ofphotovoltaic module 200 may include an inverter. In such embodiments, atransformer may be connected to an output of the inverter to provide alow voltage alternating current power supply to supply a low voltagetap. The output of such transformer may also be rectified and/orregulated (such as by an AC-to-DC converter or rectifier plus a DC-to-DCconverter) before being fed to the low voltage tap.

Wiring harness 204 and ground wiring harness 206 may advantageouslyallow photovoltaic module 200 to be quickly connected to one or moreadditional instances of photovoltaic module 200 to form an array ofphotovoltaic modules 200. Not only may wiring harness 204 and groundwiring harness 206 respectively provide electrical interface to thepositive node 228 and negative node 230 of photovoltaic module 200, theymay also serve as conductors to carry electricity generated by aplurality photovoltaic modules 200 connected together in an array.Wiring harness 204 and ground wiring harness 206 may thereby replaceexternal components such as wiring, connectors, junction boxes,breakers, etc. Stated differently, wiring harness 204 and ground wiringharness 206 may provide electrical distribution as well as electricalinterface functions.

Wiring harness 204 includes one or more conductors 216 electricallyisolated from each other within wiring harness 204. For example, wiringharness 216 is illustrated in FIG. 2 as including three conductors 216;however, wiring harness 216 can include any quantity of conductors 216.Each conductor may be used to establish a separate circuit. Positivenode 228 of photovoltaic module 200 is electrically connected to one ofthe conductors 216 by a connection subsystem (not shown in FIG. 2), asdiscussed below. The additional conductors (if any) are used solely tocarry electric current generated by other photovoltaic modules. Thus, inthe embodiment illustrated in FIG. 2, positive node 228 of photovoltaicmodule 200 is connected to one conductor 216, and the remainingconductors 216 carry electric current generated by other interconnectedphotovoltaic modules. Jumper end 218 of wiring harness 204 may be usedto connect photovoltaic module 200 to another photovoltaic module or toan electrical distribution system (e.g., a junction box). Control boxinterface end 220 of wiring harness 204 may be used to connect wiringharness 204 to a control box, as discussed below. Control box interfaceend 220 may include a quick-connect wiring connector (not shown in FIG.2) to facilitate connection to a control box accepting the quick-connectwiring connector. Such quick-connect wiring connector allows aconnection to be made without the use of solder or other time-consumingconnection schemes. Wiring harness 204 may be formed having an excesslength that can be trimmed at jumper end 218 to a length appropriate forthe application of photovoltaic module 200.

FIG. 3 is a top cross sectional view of control box interface end 220 ofone embodiment of wiring harness 204. Visible in FIG. 3 are threeconductors 216, lead 214, and an optional low voltage tap lead 222. End302 of lead 214 connects to positive node 228 of photovoltaic module200. Optional low voltage tap lead 222 connects to a low voltage tap ofphotovoltaic module 200, and is used to provide housekeeping power to acontrol box connected wiring harness 204, as discussed below.

Ground wiring harness 206 (FIG. 2) includes ground conductor 212 forproviding electrical interface to negative node 230 of photovoltaicmodule 200. Ground conductor 212 may also serve to transport electriccurrent back to the negative nodes of other photovoltaic modulesconnected to photovoltaic module 200. Similar to wiring harness 204,ground wiring harness 206 includes jumper end 224 for connectingphotovoltaic module 200 to another photovoltaic module or an electricaldistribution system (e.g. a junction box). Grounding wiring harness 206also includes connection box interface end 226 for connecting to aground connection box (not shown in FIG. 2). Connection box interfaceend 226 may include a quick-connect wiring connector (not shown in FIG.2) to facilitate connection to a ground connection box accepting thequick-connect wiring connector. Ground conductor 112 may be connected toa frame of photovoltaic module 200 or may be left floating, dependingupon building code requirements. Ground wiring harness 206 may be formedhaving an excess length that can be trimmed by cutting jumper end 224 toa length appropriate for the application of photovoltaic module 200.

Although FIG. 2 illustrates wiring harness 204 and ground wiring harness206 being disposed on opposite sides of photovoltaic module 200, each ofthe two wiring harnesses can be disposed on the same side ofphotovoltaic module 200. Furthermore, in embodiments of photovoltaicmodule 200, conductors 216 and ground conductor 212 are integratedwithin the same wiring harness (e.g., ground conductor 212 is integratedin wiring harness 204 along with conductors 216).

FIG. 4 is a block diagram of one control box 400, which is an embodimentof a connection subsystem for connecting positive node 228 ofphotovoltaic module 200 to a conductor 216 of wiring harness 204.Control box 400 is described herein with respect to components ofphotovoltaic module 200, and the following description may best beunderstood by considering FIGS. 2, 3, and 4 together.

Control box 400, for example, connects positive node 228 of photovoltaicmodule 200 to one or more of conductors 216 of wiring harness 204.Conductors 216 connect to one or more loads (e.g., an inverter), andconductors 216 may additionally connect to the positive nodes of one ormore additional photovoltaic modules 200, as shown in FIG. 5 below.Therefore, control box 400 may connect together multiple photovoltaicmodules 200 (e.g., via module-to-module connection).

Control box 400 includes conductors 404, which correspond to conductors216 of wiring harness 204. For example, control box 400 is illustratedin FIG. 4 as including three conductors 404—therefore, control box 400is intended to interface with an embodiment of wiring harness 204including three conductors 216.

Control box 400 has a connection block 402(1) for connecting control box400 to control box interface end 220 of wiring harness 204.Specifically, connection block 402(1) connects conductors 216 of wiringharness 204 to respective conductors 404 of control box 400. Connectionblock 402(1) further connects lead 214 of wiring harness 204 toconductor 406, and connection block 402(1) connects low voltage tap lead222 of wiring harness 204 to low voltage lead 418. Connection block402(1) may include quick-connect wiring connectors, crimp connectors,bolt or screw in connectors, solder connectors, braze connectors, and apush-in and capture connector.

Control box 400 also includes a connection block 402(2) for connectingconductors 404 to respective conductors 216 at jumper end 218 of awiring harness 204 of another photovoltaic module 200. Alternately,connection block 402(2) may be used to connect conductors 404 to anelectrical distribution system. Connection block 402(2) may includequick-connect connectors, crimp connectors, bolt or screw in connectors,solder connectors, braze connectors, and a push-in and captureconnector.

Electrical switch 410 is electrically connected in series with conductor406. Switch 410 is, for example, manually operated to disconnectphotovoltaic module 200 from conductors 404 and thus from flexibleconductors 216. Accordingly, switch 410 may be referred to as adisconnect switch. Current limiting device 412 is also connected inseries with conductor 406. In an embodiment, current limiting device 412prevents damage to photovoltaic module 200 and/or electricallyinterconnected components by preventing excess current from flowingthrough conductor 406 and thus through lead 214 and photovoltaic module200. Current limiting device 412 may be a fuse or other apparatus forpreventing current overload. Current limiting device 412 and switch 410may be combined in a single device such as a circuit breaker.

Conductor 406 is electrically connected to selector switch 414. In oneembodiment, selector switch 414 selectively connects conductor 406 toexactly one conductor 404, and thus electrically connects positive node228 of photovoltaic module 200 to one flexible conductor 216. In otherembodiments of control box 400, selector switch 414 is replaced with oneor more jumper wires, solder terminals, and/or other electricalconnectors to connect conductor 406 to one conductor 404. Selectorswitch 414 may advantageously allow an installer of photovoltaic module200 to select which of conductors 216 (and thereby correspondingcircuits) that positive node 228 of photovoltaic module 200 iselectrically connected to by simply adjusting selector switch 414.Accordingly, the specific circuit that photovoltaic module 200 iselectrically connected to may be adjusted without making wiring changesin embodiments of photovoltaic array 200 and control box 400. Thisfeature may simplify installation and/or configuration of a solar powergeneration system that incorporates photovoltaic module 200.

Control box 400 optionally includes performance monitoring device 416for monitoring the performance characteristics of photovoltaic module200. Embodiments of monitoring device 416 may also store performancedata and/or provide it to maintenance personnel. For example, monitoringdevice 416 may measure voltage and/or current generated by photovoltaicmodule 200, and/or the temperature of photovoltaic module 200.Monitoring device 416 may also function to detect theft of photovoltaicmodule 200 and/or damage to photovoltaic module 200. Performance datais, for example, retrieved from monitoring device 416 through wirelesstechnology such as Radio Frequency Identification (RFID). Performancedata may also be retrieved through a powerline network using conductors404 and 216, or via a data network in communication with monitoringdevice 416. Monitoring device 416 is shown with low-voltage lead 418 forproviding electrical power to monitoring device 416, and monitoringdevice 416 may be connected to conductor 406 to collect performancedata. Control box 400 may also include a cover (not shown) to protectinternal components from impact, weather, and other damage. Low voltagelead 418 may attach to a low voltage tap on an adjacent submodule 208via low voltage tap lead 222 of wiring harness 204.

Embodiments of control box 400 further include an inverter forconverting direct current (DC) electricity into alternating current (AC)electricity (e.g., 120 volts or 208 volts at 50 or 60 Hertz). In someembodiments, the inverter converts direct current electricity generatedsolely by its respective photovoltaic module 200 into alternatingcurrent electricity; in other embodiments, the inverter converts directcurrent electricity generated by a plurality of photovoltaic modules 200electrically connected to the control box into direct currentelectricity. Stated differently, in some embodiments, the inverter ispowered by a single photovoltaic module 200, and in other embodiments,the inverter is powered by a plurality of photovoltaic modules 200. Theinverter may have a single phase or a multi-phase (e.g., three phase)output. By use of an inverter, the integrated harnessing (e.g., wiringharness 204 and/or ground wiring harness 206) can now carry an AC load,thereby possibly reducing the applicability of regulations (e.g.,electrical code restrictions) directed to high-power DC circuitry.

Photovoltaic module 200 may also include an inverter that is separatefrom control box 400. Such inverter, for example, is connected in seriesbetween positive node 228 of photovoltaic module 200 and conductor 406of control box 400.

FIG. 5 is a top plan view of an array 500 of photovoltaic modules 200 ofFIG. 2. Array 500 is illustrated as including three photovoltaic modules200(1), 200(2), and 200(3); however, array 500 can include any quantityof photovoltaic modules 200 that is greater than one. Shown in FIG. 5are wiring harnesses 204 (represented by solid lines), ground wiringharnesses 206 (represented by dashed lines), and control boxes 400. Twoof the photovoltaic modules 200 of FIG. 5 are also illustrated asincluding a ground connection box 502 to facilitate connection of groundnodes among the photovoltaic modules. As noted above, in someembodiments, the ground wiring harness 206 can be included in the wiringharness 204 where voltage differences between the leads in wiringharness 204 and ground wiring harness 206 do not exceed the limits ofthe materials used to protect and insulate those leads.

The positive nodes of photovoltaic modules 200 of FIG. 5 are connectedvia wiring harnesses 204 and control boxes 400 to form a positive nodeof array 500. Specifically, the positive node of photovoltaic module200(1) is connected to the positive node of photovoltaic module 200(2)by connecting jumper end 218(1) of wiring harness 204(1) to control box400(2), and the positive node of photovoltaic module 200(2) is connectedto the positive node of photovoltaic module 200(3) by connecting jumperend 218(2) of wiring harness 204(2) to control box 400(3). Asillustrated in FIG. 5, the control box interface end 220 of each wiringharness 204 is connected to a respective control box 400. Specifically,interface end 220(1) of wiring harness 204(1) is connected to controlbox 400(1), interface end 220(2) of wiring harness 204(2) is connectedto control box 400(2), and interface end 220(3) of wiring harness 204(3)is connected to control box 400(3). The positive node of array 500 maybe connected to an electrical distribution system in order to power aload (e.g., an inverter) via jumper end 218(3) of wiring harness 204(3)or control box 400(1). In any case, the positive node of eachphotovoltaic module 200 is connected to the desired conductor in wiringharness 204 by internal wiring or switch selection in the control box400, with selection of the desired conductor dictated by the currentlimits of each conductor and the number of modules 200 selected to thatconductor.

The negative nodes of photovoltaic modules 200 of FIG. 5 are connectedvia ground wiring harnesses 206 and ground connection boxes 502 to forma negative node of array 500. Specifically, the negative node ofphotovoltaic module 200(1) is connected to the negative node ofphotovoltaic module 200(2) by connecting jumper end 226(1) of groundwiring harness 206(1) to ground connection box 502(2), and the negativenode of photovoltaic module 200(2) is connected to the negative node ofphotovoltaic module 200(3) by connecting jumper end 226(2) of wiringharness 206(2) to ground connection box 502(3). As illustrated in FIG.5, the connection box interface end 224 of each wiring harness 206 maybe connected to a ground connection box 502. Specifically, interface end224(2) of ground wiring harness 206(2) is connected to ground connectionbox 502(2), and interface end 224(3) of wiring harness 206(3) isconnected to ground connection box 502(3). The negative node of array500 may be connected to an electrical distribution system in order topower a load (e.g., an inverter) via jumper end 226(3) of ground wiringharness 206(3) or interface end 224(1) of ground wiring harness 206(1).

The required lengths of wiring harnesses 204 and ground wiring harnesses206 are a function of the spacing 504 between adjacent photovoltaicmodules 200. For example, spacing 504(1) between photovoltaic modules200(1) and 200(2) partially determines the required length of wiringharness 204(1) and ground wiring harness 206(1). Wiring harnesses 204and ground wiring harnesses 206 can be trimmed as appropriate forspacing 504 during installation of photovoltaic modules 200.

FIG. 6 is a top plan view of a solar power generation system 600including a plurality of flexible photovoltaic modules 200. FIG. 6 isdescribed herein with respect to FIGS. 2-5, and may be best understoodby considering FIGS. 2-5 together. Solar power generation system 600 is,for example, installed on a building's roof, a vehicle's outer surface,or an outer surface of a tent.

Solar power generation system 600 is illustrated in FIG. 6 as includingthree arrays 602, 604, and 606 of photovoltaic modules 200. Array 602 isillustrated as including photovoltaic modules 200(10), 200(11), and200(12); array 604 is illustrated as including photovoltaic modules200(13), 200(14), 200(15), 200(16), and 200(17); array 606 isillustrated as including photovoltaic modules 200(18), 200(19), and200(20). However, each array of photovoltaic modules 200 can have anyquantity of photovoltaic modules, and solar power generation system 600can have any quantity of arrays of photovoltaic modules. For example, inanother embodiment of solar power generation system 600 (notillustrated), array 602 includes six photovoltaic modules 200, array 604includes ten photovoltaic modules 200, and array 606 includes sixphotovoltaic modules 200. Access areas, or paths, 612 may be provided toallow access to photovoltaic modules 200 or for general site (e.g., roofor vehicle surface) maintenance.

In solar power generation system 600, each photovoltaic module includesone wiring harness 204, one control box 400, and one ground wiringharness 206. Again, the wiring harness 204 and ground harness 206 can becombined where regulations (e.g., electric code limits) permit. In FIG.6, wiring harnesses 204 are illustrated as rectangles with threevertical lines therein; control boxes 400 are illustrated as solidsquare boxes; and ground wiring harnesses 206 are illustrated asrectangles with one vertical line therein. Each photovoltaic module 200in solar power generation system 600 also includes one ground connectionbox 502, which are illustrated in FIG. 6 as having a cross hatch patternconsisting of lines disposed at two different angles.

In a manner like that of FIG. 5, positive nodes of an array photovoltaicmodules 200 are electrically connected via wiring harnesses 204 andcontrol boxes 400. Positive nodes of different arrays are, for example,connected via jumpers 614 and junction boxes 608; for example, thepositive node of array 602 is connected to the positive node of array604 via jumper 614(1) and junction box 608(1). However, as discussedbelow, the positive nodes of two or more arrays, or the positive nodesof two or more photovoltaic modules within an array, are not required tobe connected together—embodiments of solar power generation system 600may include a plurality of positive nodes.

Negative nodes are also connected in a manner like that of FIG. 5.Specifically, negative nodes of an array of photovoltaic modules 200 areconnected via ground wiring harnesses 206 and ground connection boxes502. Negative nodes of different arrays are connected via jumpers 616and junction boxes 610. For example, the negative node of array 604 isconnected to the negative node of array 606 via jumper 616(2) andjunction box 610(2).

Jumpers and junction boxes may be used to connect photovoltaic modules200 in a given array if it is impractical to connect to photovoltaicmodules using a wiring harnesses 204 and/or ground wiring harness 206.For example, two photovoltaic modules 200 in an array that are spacedsufficiently far apart such that wiring harnesses 204 and/or groundwiring harnesses 206 are too short to bridge the separation will need tobe connected using one or more jumpers and/or junction boxes. As anexample, FIG. 6 illustrates array 604 as including relatively shortphotovoltaic modules 200(15), 200(16) and 200(17) disposed aroundobstacles 618. These photovoltaic modules are disposed such that itwould not be practical to connect them via wiring harnesses 204 andground wiring harnesses 206. Accordingly, the positive nodes of thesephotovoltaic modules are connected via jumpers 614 and junction boxes608, and the negative nodes are connected via jumpers 616 and junctionboxes 610.

Junction box 608(3) provides access to the one or more positive node ofsolar power generation system 600 and junction box 610(3) providesaccess to the negative node of solar power generation system 600. Forexample, a load may be connected across junction boxes 608(3) and610(3); such load may include an inverter if one is not alreadyincorporated into the control boxes 400. It should be noted, however,that a load may connected to solar power generation system 600 at otherpoints, and the quantity and configuration of junction boxes 608 and 610as well as jumpers 614 and 616 is a design choice that will beinfluenced by various factors including the installation site of solarpower generation system 600 and/or local building codes. Metallic ornon-metallic shielding may be provided to protect wiring harnesses 204,ground wiring harness 206, jumpers 614, 616, as well as any other wiringthat might be exposed to damage, for example due to footfall, abrasion,or harsh weather, and as may be required by applicable building codes.These requirements can vary depending upon if the harnesses 204 and 206carry DC or AC power.

Each full-sized photovoltaic module 200 in solar power generation system600 generates a specific current, and each flexible circuit of system600, which is partially defined by a conductor 216 of wiring harnesses204, has a desired current rating commensurate with the needs of theload (e.g., an inverter) powered by system 600. Photovoltaic modules 200of system 600 may be sized according to country-specific standardswithout departing from scope hereof.

As stated above, wiring harness 204 may include a plurality ofconductors 216 and thereby support a corresponding plurality ofcircuits, where each conductor 216 forms part of a separate circuit. Itmay be desirable for solar power generation system 600 to include aplurality of circuits if the magnitude of electric current generated bysolar power generation system 600 is sufficiently large to make itimpractical to carry the entire magnitude via a single circuit.Furthermore, regulations (e.g., building codes) may limit the maximumcurrent that a single circuit can handle. For example, building codesmay limit a circuit's maximum current to 60 amperes (“A”). Additionally,it may be more practical to power some loads with a plurality ofcircuits rather than with a single circuit. For example, a loadconsisting of a three phase inverter may have three isolated inputswhich may be conveniently powered by three separate circuits.

Positive nodes of multiple photovoltaic modules 200 may be connected tothe same conductor 216 and thereby to the same circuit, limited only bythe current rating of the conductor and circuit. Embodiments of solarpower generation system 600 include a plurality of circuits, such asthree circuits. In such embodiments of system 600 having three circuits,the various photovoltaic modules 200 may be distributed among thesethree circuits. For example, the positive nodes of each photovoltaicmodule 200 of array 602 may be connected together to partially form afirst circuit, the positive nodes of each photovoltaic module 200 ofarray 604 may be connected together to partially form a second circuit,and the positive nodes of each photovoltaic module 200 of array 606 maybe connected together to partially form a third circuit. As discussedabove, embodiments of control box 400 allow the positive node of arespective photovoltaic module 200 to be connected to a specific circuitsimply by adjusting selector switch 414 as appropriate. For example, aplurality of photovoltaic modules 200 may be connected to a commoncircuit by setting the selector switch 414 in their respective controlboxes 400 to the same position.

FIG. 7 is an electrical schematic of one three circuit embodiment of asolar power generation system 600(1). Solar power generation system600(1) has three positive nodes 700, 702, and 704; such positive nodes,along with balance of system components and common negative node 706,form three circuits. In this embodiment, the positive nodes ofphotovoltaic modules 200 of array 602 are connected to positive node700, the positive nodes of photovoltaic modules 200 of array 604 areconnected to positive node 702, and the positive nodes of photovoltaicmodules 200 of array 606 are connected to positive node 704. In order tosupport these three circuits, wiring harnesses 204 and jumpers 614 inthis embodiment include three conductors, each of which corresponds to aseparate one of the three positive nodes or circuits.

Photovoltaic modules 200 of solar power generation system 600 may bemodified to conform to features of an installation site. For example, ifsolar power generation system 600 is installed on a rooftop, vents orother obstacles 618 may prevent full-sized photovoltaic modules frombeing installed over the entire rooftop. Photovoltaic modules 200 may bemodified to include small or custom sized photovoltaic modules, such asphotovoltaic modules 200(15), 200(16), and 200(17) as illustrated inFIG. 6. Such small or custom sized photovoltaic modules may bemanufactured to provide the same output voltage as a full-sizephotovoltaic module 200, although the small or custom sized modules mayhave a smaller current rating than the full size modules. For example,each photovoltaic module 200 in solar power generation system 600 mayhave the same open circuit output voltage, regardless of its dimensions.

FIG. 8 is an exploded side view of a flexible photovoltaic module 800.Photovoltaic module 800 is an embodiment of photovoltaic module 102 ofFIG. 1. Additionally, a wiring harness 204 and/or a ground wiringharness 206 may be added to photovoltaic module 800 to form anembodiment of photovoltaic module 200 of FIG. 2.

Photovoltaic module 800 includes a base or backplane layer 802, formounting with an installation site. Backplane layer 802 is strong,flexible, and resistant to thermal and environmental damage. Backplanelayer 802 may, for example, protect the layers of photovoltaic module800 from thermal and environmental stress. Backplane layer 802 mayinclude or provide connection to a fastener for attaching photovoltaicmodule 800 to a support structure, such as support structure 1102 ofFIG. 11. Exemplary fasteners include, but are not limited to, anadhesive, tape, screws, nails, straps or snaps, and Velcro. Backplanelayer 802 may be any suitably flexible material, such as stainless steelsheeting, plastic, or a polymer.

First pottant layer 804 overlies backplane layer 802 and supports aphotovoltaic submodule assembly 806. First pottant layer 804 and asecond pottant layer 808 form an airtight seal around photovoltaicsubmodule assembly 806 to prevent air from being trapped near activedevices (e.g., submodules or photovoltaic cells) of photovoltaicsubmodule assembly 806. Second pottant layer 808 is opticallytransparent to allow light to reach active devices of photovoltaicsubmodule assembly 806. First pottant layer 804 may be sticky or tackyto facilitate adhesion of module backplane layer 802 to pottant layer804. Similarly, second pottant layer 808 may be sticky or tacky tofacilitate adhesion of transparent top layer or upper laminate layer 810to second pottant layer 808.

In one embodiment of photovoltaic module 800, first pottant layer 804and second pottant layer 808 are formed of materials such as ethylenevinyl acetate (EVA) or polyvinyl butyral (PVB) and are applied as sheetsor sprayed onto photovoltaic submodule assembly 806. In such embodiment,backplane layer 802 and photovoltaic submodule assembly 806 are sealedto the pottant layers (e.g., by pressure or by vacuum or non-vacuumlamination). In another embodiment of photovoltaic module 800, firstpottant layer 804 and second pottant layer 808 are protective laminatesapplied to photovoltaic submodule assembly 806 with sufficient pressureor vacuum to seal the laminates without damage to photovoltaic submoduleassembly 806.

Additives may be combined with the pottant layer material to increasecut, puncture, or abrasion resistance. Additives may likewise beincorporated into the pottant layer material to change its aestheticappearance, increase its sealing properties, provide cut resistance, orenhance overall module stability and/or performance. Transparent top orupper laminate layer 810 protects photovoltaic module 800 from wear andtear and environmental stresses such as weather, ultraviolet radiation,dirt, and debris. Upper laminate layer 810 may be formed from a suitablepolymer, plastic, or other transparent, protective material, and may beapplied by lamination or by spraying. In one embodiment of photovoltaicmodule 800, transparent upper laminate layer 810 is an outer surface ofsecond pottant layer 808.

Optionally, layers of additive may be sandwiched between pottant layerson either side of photovoltaic submodule assembly 806. For example, FIG.9 shows an exploded side view of a flexible photovoltaic module 900,which is an embodiment of photovoltaic module 800. Photovoltaicsubmodule 900 includes four pottant sublayers and two additive layers.Pottant sublayer 902 is formed on base layer 802, additive layer 904 isformed on pottant sublayer 902, and pottant sublayer 906 is formed onadditive layer 904. Additionally, pottant sublayer 908 is formed onphotovoltaic submodule assembly 806, additive layer 910 is formed onpottant sublayer 908, and pottant sublayer 912 is formed on additivelayer 910.

Photovoltaic submodule assembly 806 includes a plurality of thin-film,monolithically-integrated photovoltaic cells (not shown). Suchphotovoltaic cells may be grouped into photovoltaic submodules. Thesethin-film photovoltaic cells may be produced by one or more of thefollowing thin-film technologies: copper-indium-gallium-selenium (CIGS),copper-indium-aluminum-selenium (CIAS),copper-indium-gallium-aluminum-selenium (CIGAS),copper-indium-gallium-aluminum-selenium-sulphur (CIGASS),copper-indium-gallium-selenium-sulfur (CIGSS), cadmium-telluride (CdTe),amorphous silicon (a-Si), or combinations thereof.

In one embodiment, photovoltaic submodule assembly 806 is a solar“blanket” with five or fewer monolithically integrated, interconnectedCIGS cell photovoltaic submodules. The photovoltaic submodules areconnected to achieve a final desired maximum current capability and aselected open circuit output voltage, which may be the end voltage ofeach submodule or the sum of the open circuit output voltage of eachphotovoltaic submodule. The photovoltaic submodules are, for example,120 volt photovoltaic submodules interconnected to yield a 600 voltphotovoltaic submodule assembly 806. Other possible photovoltaicsubmodule arrangements and outputs are shown in FIG. 10, as discussedbelow. The amount of power provided by photovoltaic submodule assembly806 may vary according to user needs or building codes.

Photovoltaic submodule assembly 806 is electrically connected byconductive bus bars 812. Bus bars 812 collect current from one or morephotovoltaic submodules and direct it to conductive lead 814(1), whichserves a connection to the positive node of photovoltaic submoduleassembly 806, and conductive lead 814(2), which serves a connection tothe negative node (e.g., ground) of photovoltaic submodule assembly 806.Bus bars 812 may also interconnect photovoltaic submodules withinphotovoltaic submodule layer 806 in series and/or parallel. The actualquantity and configuration of bus bars 812 will vary as a function ofthe quantity, size, and electrical interconnection of photovoltaicsubmodules within submodule assembly 806.

In one embodiment, an instance of wiring harness 204 is partiallyembedded in photovoltaic module 800 by disposing flexible electricalconductors 216 of the wiring harness laterally along the edge ofphotovoltaic submodule assembly 806. Such electrical conductors areelectrically isolated from the submodules and bus bars of photovoltaicsubmodule assembly 806.

The size and shape of photovoltaic module 800 may be modified bycomputer-aided design to fit the needs of a specific installation sitewhile maintaining appropriate electrical characteristics for thephotovoltaic module. In an embodiment of photovoltaic module 800 to beinstalled on a roof, the roof is measured and an array of photovoltaicmodules 800 is designed for maximum coverage of the roof. Photovoltaicmodules 800 are manufactured in a variety of custom sizes (e.g., fittedto optimally surround any obstructions), for example using laserpatterning. Where the roof is free from obstructions, photovoltaicmodules may be manufactured as long as regulations (e.g., buildingcodes) allow (e.g., a maximum length of one hundred and fifty feet) androlled up for easy transportation and placement (un-rolling) on theroof. Photovoltaic module 800 may be significantly lighter and moreflexible than a photovoltaic module of corresponding length made withexisting crystalline technology or technology involving integrating thinfilm on rigid substrates. Such crystalline or rigid modules would notonly be very heavy, but extremely difficult to transport or install.

It will be understood that photovoltaic module 800's dimensions arecustomizable and if the module is used in a building, its dimensions mayvary depending upon U.S. and foreign building codes. For example,building codes may limit a maximum current capability of a photovoltaicmodule to 10 amperes; in such case, the surface area of the photovoltaicmodule may be limited such that the 10 amperes maximum current rating isnot exceeded.

Where a length of an installation site has obstructions, various sizedphotovoltaic modules 800 are prepared to optimally cover the surfacearea around the obstruction. Such variable-sized photovoltaic modulesmaintain a consistent open circuit output voltage, and may thereforeinterconnect in parallel to adjacent photovoltaic modules, withoutrequiring series connection. In one example where photovoltaic modules800 are installed on a 150 foot long roof, the roof has two five-footsquare vents placed twenty feet from each end of the roof and oneeight-foot square skylight centered between the two vents. Two twentyfoot long modules and two forty-six foot long modules may be prepared tocover the 132 feet of unobstructed roof and maintain a consistent opencircuit output voltage when interconnected in parallel.

FIG. 10 schematically shows three embodiments of photovoltaic submoduleassembly 806 of FIGS. 8 and 9. Photovoltaic submodule assembly 806(1)includes a plurality of discrete narrow web photovoltaic submodules 1006that are physically and electrically interconnected. Each photovoltaicsubmodule 1006 includes a plurality of photovoltaic cells electricallyconnected in series to obtain a desired open circuit output voltage(e.g., 120 volts) of the photovoltaic submodule. Photovoltaic submodules1006 may be electrically connected in series and/or parallel such thatphotovoltaic submodule assembly 806(1) is operable to provide a desiredopen circuit voltage and a desired maximum current capability. Forexample, FIG. 10 shows photovoltaic submodules 1006 grouped into groups1008(1), 1008(2), 1008(3), 1008(4) and 1008(5), each of which includesfour photovoltaic submodules 1006 electrically connected in parallel toincrease the maximum current capability of the group. Each of groups1008 are themselves electrically connected in series to increase theopen circuit output voltage of photovoltaic submodule assembly 806(1).

Photovoltaic submodule assembly 806(2) includes a plurality of discretewide web separate photovoltaic submodules 1010, which are physically andelectrically interconnected. Each photovoltaic submodule 1010 includes aplurality of photovoltaic cells electrically connected in series suchthat each photovoltaic submodule 1010 has a desired open circuit outputvoltage (e.g., 120 volts). Photovoltaic submodules 1010 may beelectrically connected in parallel or series. An embodiment ofphotovoltaic submodule layer 806(2) has five photovoltaic submodule1010, each of which has an open circuit voltage of 120 volts. The fivephotovoltaic submodules 1010 in this embodiment are electricallyconnected in series such that photovoltaic submodule assembly 806(2) hasan open circuit voltage of 600 volts. Photovoltaic submodule assembly806(2) may be more economical to manufacture than photovoltaic submoduleassembly 806(1) because photovoltaic submodule assembly 806(2) has fewersubmodules than photovoltaic submodule assembly 806(1).

Photovoltaic submodule assembly 806(3) of FIG. 10 includes a pluralityof photovoltaic submodules 1012 monolithically integrated on a commonsubstrate. Photovoltaic submodule assembly 806(3) is a contiguousstructure with a maximum length L10 that is limited by constraints ofthe application (e.g., length of roof section), regulation (e.g.,building codes), and/or the circuit it is to be connected to.Photovoltaic submodules 1012 are illustrated as being partiallydelineated by dashed lines to indicate that photovoltaic submodules 1012are monolithically integrated onto a common substrate. Photovoltaicsubmodule assembly 806(3) may be more economical to manufacture thanphotovoltaic submodules assemblies 806(1) and 806(2) becausephotovoltaic submodule assembly 806(3) is formed of one contiguouscomponent while photovoltaic submodule assemblies 806(1) and 806(2)require the assembly of a plurality of photovoltaic submodules.

Each photovoltaic submodule 1012 of photovoltaic submodule assembly806(3) includes a plurality of photovoltaic cells electrically connectedin parallel and/or series in order to provide a desired open circuitoutput voltage and maximum current capability of the photovoltaicsubmodule assembly 806(3). An embodiment of photovoltaic submoduleassembly 806(3) includes five photovoltaic submodules electricallyconnected in series, where each photovoltaic submodule has an opencircuit voltage of 120 volts such that the photovoltaic submoduleassembly has an open circuit voltage of 600 volts.

A multitude of monolithic integration patterns may be implemented inphotovoltaic submodule assembly 806(3) to achieve a desired open circuitoutput voltage and maximum current capability. The monolithicintegration pattern may be selected in accordance with factors such asthe desired open circuit output voltage and maximum current capabilityof photovoltaic submodule assembly 806(3), the desired dimensions ofphotovoltaic submodule assembly 806(3), and/or the materials thephotovoltaic cells are formed of. Monolithic integration of photovoltaiccells of photovoltaic submodule assembly 806(3) may be computercontrolled. In such case, the monolithic integration process may beautomatically configured and controlled by computer hardware and/orsoftware used to design a solar power generation system (e.g., solarpower generation system 600) such that the monolithic integrationprocess corresponds to the solar power generation system design.Submodule scribes can be placed either along the web transportdirection, perpendicular to it, or a combination of the above.Photovoltaic submodule size can be the size of the entire photovoltaicsubmodule assembly 806(3); alternately, photovoltaic submodule assembly806(3) can be scribed into smaller photovoltaic submodules to mitigatethe impact of damage (puncture, impact, etc.) to a section ofphotovoltaic submodule assembly 806(3). The orientation of photovoltaicsubmodules within photovoltaic submodule assembly 806(3) can beoptimized through cost modeling to provide the most efficientmanufacturing process, and can accommodate separate photovoltaicsubmodules or photovoltaic submodules formed on a common substrate.

Embodiments of photovoltaic submodule assemblies 806(1), 806(2), and806(3) may be custom constructed with desired dimensions. Althoughvarious embodiments of photovoltaic submodule assemblies 806(1), 806(2),and 806(3) may have different dimensions, each embodiment may beconstructed to have essentially the same open circuit output voltage.

FIG. 11 is an exploded perspective view of a solar power generationsystem 1100. Solar power generation system 1100 includes one or moresupporting structures 1102 supporting one or more photovoltaic modules200. For example, solar power generation system 1100 may includesupporting structures 1102(1) and 1102(4) supporting photovoltaic module200(21), supporting structure 1102(2) supporting photovoltaic module200(22), and supporting structure 1102(3) supporting photovoltaic module200(23).

Supporting structures 1102 are formed of a sufficiently supportivematerial that is acceptable for the application (e.g., complies localbuilding codes if the supporting structures are used on a building). Forexample, supporting structures 1102 may be formed of foam, metal, wood,or plastic. Supporting structures 1102, for example, include slots orholes 1104, which may serve to ventilate supporting structures 1102,reduce wind lift of supporting structures 1102, and/or provide a passagefor low-voltage leads for sensors, antennas, etc.

In one embodiment, supporting structures 1102 are shaped in wedges toangle mounted photovoltaic modules 200 with respect to the surface theyare installed on (e.g., a roof) for optimal capture of incidentsunlight. Supporting structures 1102 may be light and transportable inlarge sections that are limited in size only by limitations of theselected transportation method. Photovoltaic modules 200 are for exampletransported to the installation site in rolls and unrolled into placeupon supporting structures 1102. Control boxes 400 may mount onsupporting structures 1102 for support and easy access to control boxcomponents. Ground connection boxes 502 (not shown in FIG. 11) may alsomount on supporting structures 1102.

Other embodiments of supporting structure 1102 may include a frameconstructed with suitable building materials (e.g., metals, ornon-metallic materials such as wood) or may be created by spraying orotherwise depositing insulating roofing materials around sacrificialspacers on the roof to provide a contiguous structure with multiplesurfaces upon which to mount photovoltaic modules 200. For example, FIG.12 is a side perspective view of supporting structure 1102(5), which isformed of a metal (e.g., aluminum) frame. Supporting structure 1102(5)is illustrated in FIG. 12 as supporting photovoltaic module 200(24).

Embodiments of photovoltaic modules 200 are fastenable to supportingstructures 1102. Examples of materials that may be used to fastenphotovoltaic modules 200 to supporting structures 1102 include Velcro,screws, adhesives, zip lock fasteners, or other fasteners (e.g.,fasteners acceptable under local building codes when supportingstructures 1102 are installed on a building). In one embodiment,connection flaps 1108 secure photovoltaic modules 200 to supportingstructures 1102. Connection flaps 1108 are, for example, Velcro orextensions of the substrate of photovoltaic modules 200 with adhesive onthe backplane side, that connect to receiving strips or areas 1106 ofsupporting structures 1102. Wiring harnesses 204 may interconnect andground wiring harnesses 206 may interconnect—such interconnections maybe accomplished using crimp connections, bolt or screw connectors,push-in connectors, soldering or brazing. The flexible conductors 216 ofwiring harnesses 204 may connect to inverters or a switch via controlbox 400(6), e.g., to facilitate rapid power cutoff if required by localcodes.

Changes may be made in the above methods and systems without departingfrom the scope hereof. It should thus be noted that the matter containedin the above description or shown in the accompanying drawings should beinterpreted as illustrative and not in a limiting sense. The followingclaims are intended to cover all generic and specific features describedherein, as well as all statements of the scope of the present method andsystem, which, as a matter of language, might be said to fall therebetween.

What is claimed is:
 1. A flexible photovoltaic module for convertinglight into electricity, comprising: a plurality of photovoltaic cellselectrically interconnected to form a high-voltage power outputincluding a positive node for supplying current to a load and a negativenode for receiving current from the load; a first wiring harnessincluding (a) a plurality of flexible high-voltage electrical conductorsand (b) a low-voltage electrical conductor, each of the plurality offlexible high-voltage electrical conductors being electrically isolatedwithin the first wiring harness from each other of the plurality offlexible high-voltage electrical conductors, the low-voltage electricalconductor being electrically isolated within the first wiring harnessfrom each of the plurality of flexible high voltage electricalconductors; a connection subsystem for selectively connecting thepositive node to one of the plurality of flexible high-voltageelectrical conductors of the first wiring harness; and a low-voltage tapconnected to the low-voltage electrical conductor of the first wiringharness and configured to provide a low-voltage power output from thephotovoltaic module, the low-voltage power output being separate fromthe high-voltage power output, a voltage of the low-voltage power outputbeing less than an entire voltage across the positive and negativenodes, the low-voltage tap connected to a first intermediate node of theplurality of photovoltaic cells, the first intermediate node beingdifferent from the positive and negative nodes.
 2. The photovoltaicmodule of claim 1, the connection subsystem comprising a control boxincluding at least one electrical connector for selectively connectingthe positive node to one of the plurality of flexible high-voltageelectrical conductors of the first wiring harness.
 3. The photovoltaicmodule of claim 2, the at least one electrical connector for selectivelyconnecting the positive node to one of the plurality of flexiblehigh-voltage electrical conductors of the first wiring harness being aswitch.
 4. The photovoltaic module of claim 2, the control box furthercomprising a current limiting device for limiting the flow of electriccurrent through the plurality of photovoltaic cells.
 5. The photovoltaicmodule of claim 2, the control box further comprising a disconnectswitch in electrical communication with the positive node forelectrically disconnecting the photovoltaic cells from at least one ofthe plurality of flexible high-voltage electrical conductors of thefirst wiring harness.
 6. The photovoltaic module of claim 2, the controlbox further comprising an inverter for converting direct currentelectricity produced by the photovoltaic module into alternating currentelectricity.
 7. The photovoltaic module of claim 2, the control boxfurther comprising a monitoring device for monitoring the performance ofthe photovoltaic module.
 8. The photovoltaic module of claim of 7, themonitoring device being operable to generate performance data of thephotovoltaic module and transfer the performance data to a remotelocation.
 9. The photovoltaic module of claim 1, further comprising aground wiring harness including a ground wiring conductor, the groundwiring conductor being electrically connected to the negative node. 10.The photovoltaic module of claim 9, the first wiring harness and theground wiring harness being part of a common wiring harness.
 11. Thephotovoltaic module of claim 1, the plurality of photovoltaic cellsbeing monolithically integrated on a common substrate, the commonsubstrate comprising connection flaps for fastening the photovoltaicmodule to one or more supporting structures.
 12. The photovoltaic moduleof claim 1, the low-voltage tap being electrically connected to thepositive node and to the first intermediate node of the plurality ofphotovoltaic cells.
 13. The photovoltaic module of claim 1, thelow-voltage tap being electrically connected to the negative node and tothe first intermediate node of the plurality of photovoltaic cells. 14.The photovoltaic module of claim 1, the low-voltage tap beingelectrically connected to the first intermediate node of the pluralityof photovoltaic cells and to a second intermediate node of the pluralityof photovoltaic cells, the second intermediate node being different fromthe first intermediate node.
 15. The photovoltaic module of claim 1, thelow-voltage tap comprising a DC-to-DC converter.
 16. The photovoltaicmodule of claim 1, the intermediate node being a node electricallyconnecting two of the plurality of photovoltaic cells in series.
 17. Thephotovoltaic module of claim 1, the plurality of photovoltaic cellsbeing disposed on a common backplane.
 18. The photovoltaic module ofclaim 17, the plurality of photovoltaic cells being laminated to thecommon backplane.